| 摘要 |
A strata bolt (20) for stabilising or reinforcing earth and/or rock strata comprises an axially-split tube (21) capable of peripheral expansion, and open at its outer end (21B) and an expander slug (31) for insertion into and passage along the tube to effect said peripheral expansion and effect a positive location between the bolt and the surrounding strata to provide a primary anchorage therebetween. The tube (20) at its inner end (21C) is axially split at a plurality of angularly-spaced locations (25) at its inner end and is of reduced inner cross-sectional area at its inner end whereby the primary anchorage due to the action of the expander slug is effected at the inner end of the strata bolt. There is preferably one anchorage slug and a plurality of pressure slugs (32), the latter being of various sizes in cross-sectional area but all of larger cross-sectional area than the anchorage slug. |
